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1990年,哈勃天文望远镜被发射上天。从此,它开始在离地球600千米的高空绕着地球转。让我们一起跟随哈勃天文望远镜来探索宇宙的奥秘吧。
In 1990, the Hubble telescope was launched. From then on, it began to orbit the earth at an altitude of 600 kilometers from the earth. Let us follow the Hubble telescope to explore the mysteries of the universe.